Geological Societi). \ 37 



analogous to that described by Mr. Lyell as now taking place on the 

 shores of tlie Baltic*. 



Of the period when the change was effected, Mr. Smith offers no 

 conjecture ; but he states that it must have been anterior to the oc- 

 cupation of Britain by the Romans, because the terminations of their 

 wail on the shores of the Forth and the Clyde were constructed with 

 reference to the present level of the sea. He also adds, that on the 

 banks of the Firth of Clyde there are vitrified forts andtumuli to which 

 the same observation applies; and that no human remains or works 

 of art have been found in the clay. 



At his first examination, the author concluded, judging from the 

 sea-worn terraces which skirt the coasts, that the change of level 

 could not exceed 40 feet, but he has since observed the clay at the 

 height of 50 feet J and Mr. Buchanan of Arden has found oyster- 

 shells near Loch Lomond 70 feet above the sea. Mr. Smith, how- 

 ever, believes that at the period when the clay was accumulated and 

 the terraces formed, the relative level of sea and land was stationary, 

 and that, if we may judge from the comparative dimensions of the 

 ancient terraces with those now forming, the period during which the 

 level was thus stationary must have greatly exceeded 2000 years. 



The important question, if the Fauna and Flora of the period when 

 this deposit was accumulated were identical with those of the present 

 epoch, Mr. Smith says it would be premature now to determine. A 

 very great proportion of the species of shells, amounting in all to about 

 70, abound in the present seas; and it is worthy of remark that Astarie 

 Ga;e«5w, which is common in the clay at Helensburgh, is found in 

 great numbers in the Gare Loch ; on the other hand, some of the 

 species have become very rare, if not extinct with reference to the 

 coast of Scotland. 



In alluding to the geological position of the upper deposit, the 

 author says, that it must be placed among the newer pliocene 3 and 

 as it belongs to one of the first steps in the descending series, every 

 circumstance connected with it should be carefully observed and re- 

 corded, that researches into the more ancient formations may be con- 

 ducted with greater success. 



A paper was afterwards read ** On the distribution of Organic 

 Remains in the Oolitic formations on the coast of Yorkshire," by 

 W. C. Williamson, Esq., Curator of the Natural History Society of 

 Manchester, and communicated by the President. 



In a former paperf Mr. Williamson gave detailed sections of the 

 lias in the Yorkshire coast, with a view to determine how far its fossils 

 might be useful in recognising the different beds of the formation at 

 other localities. The paper read at this meeting was prepared with 

 the same intent, and gave detailed accounts of the fossils of the (1) 

 inferior oolite, (2) the lower shale and sandstone, and the (3) Great 

 or Bath oolite. 



1 . The point selected by Mr. Williamson as affording the best section 



* Phil. Trans., 1835, p. I. 

 t Lend, and Edinb. Phil. Mag., vol. v. p. 222. 

 Third Series. Vol. 10. No. 59. Feb, 1837. T 



